In the related art, an apparatus including independent scintillators for each pixel of a two-dimensional optical sensor is known. For example, in Patent Literature 1, there is disclosed a radiation detection apparatus including an optical detection panel having a plurality of pixels formed on a substrate, wherein a plurality of convex patterns are formed on at least one pixel of the plurality of pixels on the optical detection panel, and columnar crystals of the scintillator are grown on upper surfaces of the plurality of convex patterns.
In addition, in Patent Literature 2, there is disclosed an X-ray plane detector including a plurality of pixel units arranged in a two-dimensional array, wherein each of the pixel units has a scintillator unit configured to convert X-rays entering from a predetermined input surface into light, and interruption regions formed between the scintillator units of the adjacent pixel units such that the scintillator units are not continuous. The interruption regions are formed by forming grooves throughout the entire width of a scintillator layer through radiation of the laser beam to the scintillator layer. In Patent Literature 3, there is disclosed an X-ray imaging apparatus including a scintillator layer divided into optically independent pixels by grooves formed by laser ablation.